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The Antarctic Ice Sheet (AIS) has been losing ice mass and contributing to global sea level rise (GSLR). Given its mass that is enough to cause ∼58 m of GSLR, accurate estimation of mass balance trend is critical for AIS mass loss monitoring and sea level rise forecasting. Here, we present an improved approach to reconciled solutions of mass balance in AIS and its regions from multiple contributing solutions using the input-out, altimetric, and gravimetric methods. In comparison to previous methods, such as IMBIE 2018, this approach utilizes an adaptive data aggregation window to handle the heterogeneity of the contributing solutions, including the number of solutions, temporal distributions, uncertainties, and estimation techniques. We improved the regression-based method by using a two-step procedure that establishes ensembled solutions within each method (input-output, altimetry, or gravimetry) and then estimates the method-independent reconciled solutions. For the first time, 16 contributing solutions from 8 Chinese institutions are used to estimate the reconciled mass balance of AIS and its regions from 1996 to 2021. Our results show that AIS has lost a total ice mass of ∼3213±253 Gt during the period, an equivalent of ∼8.9±0.7 mm of GSLR. There is a sustained mass loss acceleration since 2006, from 88.1±3.6 Gt yr−1during 1996–2005 to 130.7±8.4 Gt yr−1during 2006–2013 and further to 157.0±9.0 Gt yr−1during 2014–2021. The mass loss signal in the West Antarctica and Antarctic Peninsula is dominant and clearly presented in the reconciled estimation and contributing solutions, regardless of estimation methods used and fluctuation of surface mass balance. Uncertainty and challenges remain in mass balance estimation in East Antarctica. This reconciled estimation approach can be extended and applied for improved mass balance estimation in the Greenland Ice Sheet and mountain glacier regions.

In the process industry, online product quality prediction is crucial for effective quality control. However, the highly nonlinear and dynamic nature of monitoring data, characterized by temporal-spatial relationships, brings great challenges to product quality prediction. To address this issue, a novel model is proposed for short-term prediction of product quality in process industries. This model employs a parallel attention mechanism to extract weight coefficients from raw data’s temporal and feature dimensions. Subsequently, a 1-D CNN with SeLU activation performs spatial correlation extraction and noise filtering. The processed time series data is then effectively modeled by a BiLSTM network. Finally, a dense network realizes short-term prediction of product quality. The proposed model was evaluated using data from coal processing scenarios and water quality predictions. The results demonstrated superior multistep prediction accuracy and stability compared to existing models, including BiLSTM, CNN_BiLSTM, and Attention_CNN_BiLSTM. This study proposes a deep learning approach that effectively addresses product quality nowcasting in the process industry, achieving satisfactory prediction performance.

The purpose of this study was to investigate the feasibility of constructing an oral delivery system for quercetin (QUT) using hyaluronic acid (HA) as the wall material. The findings revealed that when the mass ratio of QUT to HA was 1:10, the prepared QUT-HA complexes exhibited excellent stability (particle size of 802 nm, zeta potential of −36 mV) and QUT loading capacity (encapsulation efficiency of 79.77%, loading capacity of 89.65 mg/g). The characterization of QUT-HA complex confirmed the formation of hydrogen bond between QUT and HA, resulting in a homogeneously dispersed coral-like complex and leading to the transformation of QUT's crystal structure into an amorphous state. Environmental stability analysis demonstrated that the QUT-HA complex maintains good stability within an ionic concentration range of 0–500 mM, a pH range of 3–8, and at temperatures of 50–90 °C. In vitrosimulations of gastrointestinal digestion indicated that the QUT-HA complex aggregates during simulated gastric fluid digestion and dissociates following simulated intestinal fluid digestion, effectively enhancing the bioaccessibility of QUT. Antioxidant assays showed that the scavenging ability of QUT against DPPH and ABTS radicals was significantly improved by complex loading. Therefore, the QUT-HA complex developed in this study possesses a high QUT loading capacity, excellent processing and digestive stability, and can effectively enhance the bioaccessibility and antioxidant activity of QUT, making it a promising candidate for use as an oral nutritional supplement in the field of functional foods.

Laurencia undulata, as one of the most biologically active species in the genus Laurencia, is an edible folk herb red algae. Among them, d-isofloridoside (DIF, 940.68 Da) is isolated from Laurencia undulata, which has antioxidant and matrix metalloproteinases (MMP) inhibitory activities. However, its mechanism of action on tumor angiogenesis has not yet been reported. In this study, we have studied the mechanism of DIF on tumor metastasis and angiogenesis in HT1080 cell and human vascular endothelial cell (HUVEC). The results show that DIF can reduce the activity of MMP-2/9, and can inhibit the expression of hypoxia-inducible factor-1α (HIF-1α) by regulating the downstream PI3K/AKT and mitogen-activated protein kinases (MAPK) pathways, thereby down-regulating the production of vascular endothelial growth factor (VEGF) in CoCl2-induced HT1080 cell. In addition, DIF can inhibit the activation of VEGF receptor (VEGFR-2), regulate downstream PI3K/AKT, MAPK, nuclear factor-kappa B (NF-κB) signal pathways, activate apoptosis, and thus down-regulate the production of platelet-derived growth factor (PDGF) in VEGF-induced HUVEC. In conclusion, our research shows that DIF has the potential to develop into a tumor-preventing functional food and tumor angiogenesis inhibitor, and it can provide theoretical guidance for the high-value comprehensive utilization of edible red algae Laurencia undulata.

The coexistence of nanoplastics (NPs) and various pollutants in the marine environment has become a problem that cannot be ignored. NPs and marine algae toxins are found in marine organisms and both can enter the human body through the food chain. However, the joint toxic effects of marine algae toxins and NPs on human health remain unknown. In this study, the joint toxic effects and mechanisms of polystyrene (PS) NPs and okadaic acid (OA) were investigated on human gastric adenocarcinoma (AGS) cells. AGS cells were exposed to 20 nm PS (0.5, 8 μg mL−1) or/and OA (5, 10 ng mL−1), and their cytotoxicity was assessed by measuring relevant indicators, transcriptomics, and weighted gene co-expression network analysis (WGCNA). Our data indicated that the joint toxicity of PS and OA to AGS cells was mainly characterized by a decrease in cell viability, depolarization of mitochondrial membrane potential, and a decrease in IL10 and p53 protein activity, accompanied by an increase in intracellular ROS production and calcium and IL8 levels in comparison with single contaminants. In addition, co-exposure to PS and OA caused cellular damage by activating PI3K/AKT, ERK/c-FOS and caspase-3/caspase-9 signaling pathways. Moreover, the high concentration of PS significantly enhanced the toxicity of OA. WGCNA highlighted enrichment in the Fanconi anemia pathway and MAPK signaling pathway and identified that IER3was the hub gene in PS and OA co-exposed AGS cells. The results of this study provided insights into the joint toxicity evaluation of NPs and marine algae toxins.

Microalgae are primary producers with multiple nutrients in aquatic environments and mostly have applications in biological feed and fuel industry. There are few studies assessing the angiotensin-I-converting enzyme (ACE) inhibition potential of Isochrysis zhanjiangensis, other than its antioxidant potential. In this study, we evaluated a peptide from I. zhanjiangensis(PIZ, FEIHCC) and its vascular endothelial factors and mechanism in human umbilical vein endothelial cells (HUVEC). The results reveal that PIZ (IC50= 61.38 μM) acts against ACE in a non-competitive binding mode. In addition, PIZ inhibits angiotensin II (Ang II)-induced vascular factor secretion and expression by blocking inflammation and apoptosis through nuclear factor κB (NF-κB), nuclear erythroid 2-related factor 2 (Nrf2), mitogen-activated protein kinases (MAPKs), and the serine/threonine kinase (Akt) signal pathways. This study reveals that PIZ has potential to be developed as a therapeutic agent for hypertension and provides a new method of high-value utilization of I. zhanjiangensis.

The transport of ionic species through nanochannels plays an important role in the basic research and practical application of nanofluidic devices. Here, a visualized CdSe@ZIF-8/PAA nanochannel membrane was created by employing in situ growth of zeolite imidazole skeleton (ZIF-8) and CdSe quantum dots (CdSe QDs) on a porous anodized aluminum oxide (PAA) membrane surface using CdSe QDs, 2-methylimidazole, and zinc nitrate as the precursor solvents. ZIF-8 is a kind of metal–organic framework, a microporous material that possesses strong metal adsorption capacity. In addition, CdSe quantum dots have fluorescent properties. The nanochannel membrane detects copper ions (Cu2+) by quenching the fluorescence intensity by the interaction between Cu2+and Se and S atoms. The direct potential of 5 V was applied to achieve Cu2+enrichment at the nanochannel interface, and the fluorescence change was observed. The CdSe@ZIF-8/PAA nanochannel membrane has a good linear range of concentration (0.01 pM–1 μM) for Cu2+detection. With the help of nanochannel enrichment, its detection limit reaches 4 fM. In addition, this nanochannel membrane has good selectivity for Cu2+.

Abalone (Haliotis discus hannai) is a precious seafood in the market. It has been reported that biological active substances derived from abalone have anti-oxidative, anti-inflammatory, anti-bacterial, and anti-thrombosis potential. However, there were few studies to assess whether they have anti-cancer potential. In this study, we evaluated the anti-metastasis and anti-pro-angiogenic factors and mechanism of action of boiled abalone byproduct peptide (BABP, EMDEAQDPSEW) in human fibrosarcoma (HT1080) cells and human umbilical vein endothelial cells (HUVECs). The results demonstrated that BABP treatment significantly lowers migration and the invasion of HT1080 cells and HUVECs. BABP inhibits phorbol 12-myristate 13-acetate (PMA)-induced matrix metalloproteinase (MMP) expression and activity by blocking mitogen-activated protein kinases (MAPKs) and NF-κB signaling and hypoxia-induced vascular endothelial growth factor (VEGF) secretion and hypoxia inducible factor (HIF)-1α accumulation through suppressing the AKT/mTOR signal pathway. BABP treatment inhibits VEGF-induced VEGFR-2 expression and tube formation in HUVECs. The effect of BABP on anti-metastatic and anti-vascular activity in HT1080 cells and HUVECs revealed that BABP may be a potential pharmacophore for tumor therapy in the future.

The transport of ions in nanochannels has received considerable interest owing to the unique transport properties and potential applications. In this study, ultrasmall nanochannels (0.8–1.2 nm) were fabricated in porous anodized aluminum (PAA) membrane in situ growth. 2-Methylimidazole and zinc nitrate were used as the reaction precursor solkution, and then zeolitic imidazolate framework (ZIF-8) nanoparticles were sufficiently filled in PAA nanochannels to form a ZIF-8/PAA nanochannels composite membrane. Because ZIF-8 is a microporous material and has a strong ability to adsorb heavy metals, the composite membrane was used as a biosensor to detect lead ion (Pb2+) by the coordination interaction between Pb2+and nitrogen atoms. The detection limit reached to 0.03 nM due to the enrichment of nanochannels under electric field. The sensor has a good linear range for Pb2+from 10 nM to 10 μM.

ABSTRACTWidespread movement of meltwater has been found on the Amery Ice Shelf (AIS). Intensive surface snowmelt could accelerate ice loss and endanger the ice shelves under climate warming. In this study, the Advanced Scatterometer (ASCAT) was used to study the detailed melt patterns on the AIS, which was confirmed by the wet snow mapped by Sentinel-1 Synthetic Aperture Radar (SAR) images with a much higher spatial resolution. Melt seasons were longer than 50 days in the eastern part of AIS. Conversely, a large proportion of the western AIS only melted occasionally for several days with the exception of blue ice areas. Two obvious snowmelt patterns are found on the AIS. First, the opposing summer katabatic wind directions on the eastern and western sides of the AIS result in a warmer eastern AIS compared with the western side, which leads to the expansion of snowmelt from east to west on the AIS. Second, intense snowmelt was found in the grounding zone with low-albedo blue ice and rock outcrops. However, ASCAT fails to detect snowmelt in these places due to the dominated surface radar scattering. AIS melt patterns are determined by both meteorological conditions and the underlying surface.

The interaction of air‐ice‐ocean‐biology plays a key role in the global environment and sea‐level changes. The basal channel at the bottom of the Amery Ice Shelf (AIS) and the Mackenzie polynya are the intense sites for the interaction of air‐ice‐ocean‐biology in the Prydz Bay. In this study, the spatio‐temporal distribution characteristics of the complex basal channel system from the 1990s to 2019 are discovered and analyzed. The shapes of the channels are inverted‐V in the deep parts, gradually becoming inverted‐U as it develops in accordance with the direction of erosion. The deepest part of the basal channel system is over 800 m resulting from the meltwater plumes at the southernmost grounding zone. The linear and thinner channel region is the weakest and most sensitive part under ocean forcing leading to instability of the AIS (e.g., longitudinal fractures and calving). Conductivity‐temperature‐depth data are used to confirm the paths and shapes of the warm and cold water in the interaction. Channels can be divided into warm and cold‐water channels based on filled water masses. Cold water channels collect the fresh melting water and drain it out. Paths of cold‐water columns from different channels extend to the Mackenzie polynya area, which prevents warm water from entering the west AIS. Meltwater from the channels, warm water, brine produced by the Mackenzie polynya, and marine mammals in the polynya together constitute a complex regional environment system of dynamical air‐ice‐ocean‐biology interactions. The Amery Ice Shelf (AIS), ocean, and Mackenzie polynya compose a regional air‐ice‐ocean‐biology environment system, which is connected by basal channels. Basal channels are deep upward grooves at the base of ice shelves. Polynyas are open water surrounded by sea ice and release brine while producing sea ice. Remote sensing data are used to study the distribution and characteristics of basal channels and the threat on the AIS stability. The deepest channel is over 800 m, which is the deepest among any reported ice shelf basal channels. The shapes of channels are inverted‐V in the deep parts, and gradually become inverted‐U as the channels develop; these shapes are related to the type of ocean erosion. Supercooled meltwater carrying ions is discharged through the channels on the western AIS, which blocks the invasion of warm water and provides materials for primary productivity of the Mackenzie polynya. The brine released in Mackenzie polynya has considerable impacts on the basal melting of the AIS and circulation in the Prydz Bay. Basal channels and the Mackenzie polynya affect the local environment by weakening the stability of the AIS and altering the characters and paths of water masses. The complex basal channel system beneath Amery Ice Shelf (AIS) is a sensitive area for the ocean forcing on ice shelf stabilityThe variations of channels' shape and size in different areas related to the erosion pattern of seawaterBasal channels collect the fresh melting water and drain it out the ice shelf, which prevents warm water entering the west AIS The complex basal channel system beneath Amery Ice Shelf (AIS) is a sensitive area for the ocean forcing on ice shelf stability The variations of channels' shape and size in different areas related to the erosion pattern of seawater Basal channels collect the fresh melting water and drain it out the ice shelf, which prevents warm water entering the west AIS

The microstructure of hydroxyapatite is known to influence cellular behavior, can be used as a substrate for osteoblast growth, and exploited as a drug-release platform. However, easy delamination and self-decomposition of hydroxyapatite caused by poor adhesion with substrates are the main problems currently. In this paper, we successfully fabricated titanium dioxide/strontium-doped hydroxyapatite (TiO2/SrHA) composite scaffolds by self-generated strontium-substituted hydroxyapatite microspheres in TiO2nanotubes. Moreover, the active compound 1-(5-bromo-2-hydroxy-methoxyphenyl)-ethanone (BHM) from Seahorse (Hippocampus kudaBleeler) was loaded in this scaffold, and the controlled release kinetics of BHM was studied. It was found that in the first 5 h, the release concentration and time of BHM had a good linear relationship, and the correlation coefficient reached 0.98. TiO2/SrHA/BHM composites exhibited favorable cytocompatibility at a given concentration of BHM (20 μmol/L). Compared to pure SrHA, TiO2nanotubes, and traditional TiO2/SrHA composites, superior cytocompatibility (cell adhesion and proliferation) of MC3T3-E1 was obtained on TiO2/SrHA/BHM composites. The expression levels of osteogenic marker genes such as alkaline phosphatase, osteopontin, osteocalcin, runt-related transcription factor 2, and collagen I are also upregulated to varying degrees. This TiO2/SrHA composite scaffold-mediated phenolic compound BHM could be applied in bone tissue repair.

A novel mercury ion (Hg2+) electrochemical sensor was established via chemical modification of porous anodic alumina (PAA) membrane nanochannels with DNA. PAA membrane was prepared by a two-step anodization. Amino groups were introduced to nanochannels by silanization. Special sequence DNA (along with amino group) was modified on PAA membrane nanochannels by the condensation reaction of amino and aldehyde groups. Electrochemical detector was built via sputtered Au nanoparticles on the surface of PAA nanochannels, which could be used as working electrode. The reduction potential of 0 V was applied, where the flux of Fe(CN)63[?] was determined by diffusion. The current response has a positive correlation with the concentration of Fe(CN)63[?]. After DNA immobilized, the negative charge and the steric hindrance of the nanochannels is increased, resulting in the decreasing of the flux of Fe(CN)63[?]. The detection current is reduced compared with pure PAA membrane nanochannels. When Hg2+ is present, a stable thymine-Hg2+-thymine structure is formed due to the specific reaction between thymine in DNA and Hg2+. In this case, the charge density and steric hindrance of the nanochannels are decreased, thereby increasing the flux of Fe(CN)63[?] and restoring current. The results show that the detection limit is about 0.08 pM with a good linear response (from 1 pM to 100 nM). Meanwhile, the sensor has a good selectivity. The current responses of other metal ions (Mn2+, Mg2+, Ba2+, Co2+ and Cd2+) are not obvious compared with Hg2+. Therefore, this new sensor could be applied for detecting Hg2+ in the environment.

Microalgae are important biological sources of marine active peptides and renewable biological resources. Isochrysis zhanjiangensishas been widely used in biological ultrafiltration membranes and aquaculture. However, there are relatively few studies on its component structure and diverse activities. In this study, the mechanism of action of previously isolated pentapeptides (AYP, Ala-Tyr-Ala-Pro-Glu) on inflammation and tumor angiogenesis was evaluated. The results showed that AYP could effectively inhibit the invasion and migration of human umbilical vein endothelial cells (HUVECs) and HT1080 cells by downregulating the expression of MMP-2/-9, independent of cytotoxicity. Especially after 100 μM AYP treatment, the ability to inhibit migration was about 67.7% ± 1.9 for HT1080 cells and 63.6% ± 1.3 for HUVECs, respectively. In addition, the activity of iNOS and COX-2 was decreased by inhibiting the oversecretion of VEGF in HT1080 cells induced by CoCl2and the activation of VEGFR-2 in HUVECs and by regulating PI3K/AKT and Ras/MAPK signaling pathways. It can prevent inflammation and block tumor angiogenesis. Therefore, AYP is expected to become a drug or functional food to prevent and treat tumor angiogenesis.

In this study, we aimed to verify the effectiveness of fermentation as a pretreatment in Nile tilapia (Oreochromis niloticus) skin gelatin production and to assess its effects on the extracted gelatin. Chemical-gelatin (CG) and fermentation-gelatin (FG) were extracted using hot water from tilapia skin after immersion in chemical reagents (sodium hydroxide and butanol) and after fermentation with Bacillus velezensisFEL-BM21, respectively. FG presented a higher recovery (27.40%), yield (49.99%), and imino acid (proline and hydroxyproline) content (177.17 ± 0.35 residues/1000 residues) than CG, but had a lower molecular weight. Fourier transform infrared and circular dichroism spectroscopy confirmed that the collagen was denatured, and scanning electron microscopy revealed that FG had a more continuous filamentous structure than CG. Furthermore, except for transmittance (66.19% at 450 nm and 86.36% at 620 nm), FG exhibited higher gel strength (492.81 g), gelling point (28.93 °C), and melting point (18.33 °C) than CG. These findings suggest that fermentation can be used to treat gelatin raw materials without negatively affecting the structure of gelatin. Moreover, fermentation has potential industrial applications as an alternative to chemical treatment.

DNA vaccine has become an attractive approach for generating antigen-specific immunity. Targeting antigens to FcRs for IgG (Fc_Rs) on dendritic cells (DCs) has been demonstrated to enhance antigen presentation. Secondary lymphoid tissue chemokine (SLC) has been shown to increase immune responses not only by promoting co-clustering of T cells and DCs in the lymph nodes and spleen but also by regulating their immunogenic potential for the induction of T cell responses. In this study, using HPV 16 E7 as a model antigen, we constructed a chemotactic-antigen plasmid DNA vaccine (pSLC-E7-Fc) by linking SLC and Fc gene sequences to each end of E7 and evaluate its potency of eliciting specific immune response. We found that immunization with pSLC-E7-Fc generated much stronger E7-specific lymphocyte proliferative and cytotoxic T lymphocyte (CTL) responses than control DNA. All the mice receiving pSLC-E7-Fc prophylactic vaccination remained tumor free upon subcutaneous inoculation of TC-1 cells, while those given control DNA all developed tumors. These tumor-free mice were also protected against TC-1 re-challenge. Complete tumor regression with long-term survival occurred in 72% of mice given pSLC-E7-Fc as therapeutic vaccination. In experimental lung metastasis model wherein TC-1 cells were intravenously injected, therapeutic vaccination with pSLC-E7-Fc significantly reduced the number of tumor nodules in the lung. In vivo depletion with antibodies against CD4+ or CD8+ T cells both resulted in complete abrogation of the pSLC-E7-Fc-induced immunotherapeutic effect. Our data indicate that the DNA vaccine constructed by the fusion of SLC and IgG Fc fragment genes to antigen-coding gene is an effective approach to induce potent anti-tumor immune response via both CD4+ and CD8+ T cells dependent pathways.

In this study, 2,3-dialdehyde starch crystal was used as a novel and low-toxicity bio-crosslinker to design composite gelatin-based films with both superior mechanical and barrier properties. The starch crystal containing aldehyde group was fabricated viaperiodate oxidation as an efficient cross-linker to reinforce the gelatin-based bio-composite films. X-ray photoelectron spectroscopy (XPS) and 1Hydrogen nuclear magnetic resonance (1H-NMR) revealed that di-aldehyde starch crystal (Di-SC) could react and covalently cross-link with the amine group of gelatin molecules viaC=N chemical bond. The tensile strength of gelatin film containing 10% di-aldehyde starch crystal (G/Di-SC-10%) exhibited a tensile strength of 70.8 MPa, which was 967% higher than that of neat gelatin film (6.7 MPa). Additionally, the hydrophobic properties, thermal stability and surface morphology of G/Di-SC-10% were significantly enhanced, and so was its UV-barrier shield efficiency. Our results indicate that the new gelatin/di-aldehyde starch crystal bio-composite film has potential practical applications in the edible film-based packaging industry.

A novel mercury ion (Hg2+) electrochemical sensor was established via chemical modification of porous anodic alumina (PAA) membrane nanochannels with DNA. PAA membrane was prepared by a two-step anodization. Amino groups were introduced to nanochannels by silanization. Special sequence DNA (along with amino group) was modified on PAA membrane nanochannels by the condensation reaction of amino and aldehyde groups. Electrochemical detector was built via sputtered Au nanoparticles on the surface of PAA nanochannels, which could be used as working electrode. The reduction potential of 0 V was applied, where the flux of Fe(CN)63−was determined by diffusion. The current response has a positive correlation with the concentration of Fe(CN)63−. After DNA immobilized, the negative charge and the steric hindrance of the nanochannels is increased, resulting in the decreasing of the flux of Fe(CN)63−. The detection current is reduced compared with pure PAA membrane nanochannels. When Hg2+is present, a stable thymine-Hg2+-thymine structure is formed due to the specific reaction between thymine in DNA and Hg2+. In this case, the charge density and steric hindrance of the nanochannels are decreased, thereby increasing the flux of Fe(CN)63−and restoring current. The results show that the detection limit is about 0.08 pM with a good linear response (from 1 pM to 100 nM). Meanwhile, the sensor has a good selectivity. The current responses of other metal ions (Mn2+, Mg2+, Ba2+, Co2+and Cd2+) are not obvious compared with Hg2+. Therefore, this new sensor could be applied for detecting Hg2+in the environment.